fuzzer_corpus: A corpus of files to be tested against all fuzzer targets

Overview

fuzzer_corpus is a centralized directory with files that are used for testing fuzzer targets during unittest phase.

Warning

Be careful when adding large number of files here. This is in the platform2 repository and is checked out with many projects. So the larger it gets, the heavier checking out the platform2 repository will be. If decided to add many files (specially large ones), we have to plan to move this into a separate repository of its own.